DAVAO, Philippines - Search and rescue efforts continued Monday at a three-story building in the southern Philippines that collapsed in a strong earthquake.

The Bureau of Fire Protection said six people have been rescued from the building in Davao del Sur province's Padada town since Sunday's magnitude 6.9 quake.

Officials have yet to give an estimate of how many people may be inside the building, which housed a grocery story.

Army troops, police and firefighters were all involved in the search operation.

The Bureau of Fire Protection said the death toll from the quake had climbed to two, after a woman in her 70s was found to have had a heart attack during the quake. A 6-year-old was earlier reported killed after a wall collapsed.

Another 84 people were injured in the quake, officials said.

Four towns and one city near the quake were still without power Monday, and school was cancelled in a broad area to give time for inspections of the buildings.

The Davao region has been hit by several earthquakes in recent months, causing some deaths and scores of injuries and badly damaging houses, hotels, malls and hospitals.

The Philippine archipelago lies on the so-called Pacific “Ring of fire,” an arc of faults around the Pacific Ocean where most of the world's earthquakes occur. It's also lashed by about 20 typhoons and other severe storms each year, making the Southeast Asian nation of more than 100 million people one of the world's most disaster-prone countries.